Furnace



E. H. DAU

Nov. l2, 1940.

FURNAGE Filed May 2, 1938 2 Sheets-Sheet l Nov. 12, 1940. E. H. DAU 2,221,471

FURNACE Filed May ze, 1938 2 sheets-sheet 2 /4A FIE@ /f /5 20 Patented Nov. 12, 1940 s, f UNITED STATES PATENT FFICE i u u, .2,221,471" f f l FURNACE Eberhard H. Dau,v Dormont,` Pa. Appiicatien May 2, 193s, serial No. 205,642

s u claimst (o1. 26a-40) This invention relates to furnaces such as used for `heating metalfarticles and Amaterials and,

particularly, to )an improved furnace for `such l use in which the heating chamber canbe varied in size as desired.

"Heretofore, in the heating of metallic articles or materials in such furnaces, it was usually necessary to heat the entire heating chamber of the furnace, no matter `how small orhow great the charge to be heated.

In heating small quantities of materiaLonly thatimmediate vicinity `of the chamber which ythe material occupies need. be heated, but it has been necessary to` heat the entire chamber in order to obtain the desired temperature to properly heat the material; which resulted in heating, unnecessarily,` a large portion of the unused chamber. .It would, of course, haveb'een advantageous to make up a full load or charge before heating, in order to obtain the most efficient use of the heating gases but this was not always possible, due to the length ofV the materialsor articles to be heated or `due to the type of heat treatment required for `any particular charge.

This'unnecessary heating of the unused' por# tion ofthe heating chamber resulted in a need# less wasteV of fuel and increased the length `of time `of treating. y s

According' to `the present invention, the size of the heating chamber of such furnaces can be increased or decreased, as desired, by placing re gates or doors at predetermined positions in `the heating chamber to separatel the portion 0f thechamber to be used forheattreatingany particular charge from that portionnot to be used.` i

It is one of. the objects of the present inven` tion `to provide an improved `type furnace for heating metallic articles andmaterials having a heating chamber which` can beA adjusted relative to the size of the charge 1or load to b e heated.

lIt is another object of the invention to pro.- vide fafurnace which will heat metallic articles and materials both efficiently andeconomically with aminimum amount of loss of heat and con- Various other objects and advantages of this of the same;

Figure 3 is a section taken on line III-IIL of Figure 2; t

Figure 4 is a` section taken on line IV-IV1of i Figure 3; i i 15 Figure 5 is a section taken on line V--V of Figure 3, and,`

i Figure 6 is a section through part of the door and side wall of the furnace, showing a modified construction of the guide and supporting grooves. 20

There is shown in the drawings a conventional type furnace for heating metallic articles and materials with which myk invention is incorporatecl. This furnace comprises side walls 2,

a flooror bottom 4, a top or roof 5, a perma- 2`5 k nently closed end wall 3 at oneend thereof, a movable'door or gate 6 at theopposite or charging end, and an elongated heating chamber 'Il yA furnace `of this type isV usually gas-fired by means of a plurality of spaced burners 8 positioned in 30 each of the sidewalls thereof,`which are con` trolledby means of a similar number `of valves`9.

V According to the invention there is arranged at predetermined spaced intervals within the heating chamber on the inside of the side walls, 85 sets `of oppositely` disposed guide grooves IIJ, which are preferably `beveled toward the charging end ofthe furnace and extend at an acute angle with the floorof the furnace and an `equal number of laterally extending similarly beveled 40 grooves I2 which are aligned with the `bottom `end of theguide grooves I Il betweenfthe side walls. There is positioned, preferably on the top of the furnace above each set of guide grooves opposite openings II in the roof ofthe furnace, a frame I3 having guide grooves carried thereby which are aligned with the guide grooves `IIJ of the side walls of the heating chamber for guiding and supportingva fire gate orv door I4. Thisframe also carries preferably a pulley I5 over 50 whicha chain or `rope I6 is adapted to be actuated;` Thechain or rope is suitably connected to the top of a door and is provided for the purpose of raising or lowering `the doors I4 into and out of the heating chamber 1, as desired.

The fire gate or door M, as shown in Figures 4 and 5, comprises a heat resisting or insulating material Il, such as nre brick or, preferably, Sil-O-Cel brick, having a heat resisting metallic sheet I8 on one side thereof and, preferably, a 10W carbon metallic sheet I9 on the opposite side thereof, with a channel-like cast iron or heat resisting metallic frame 20 therearound. The door is constructed in this manner so as to prevent Warpagetthereofduetothe heat.` The bottom of the frafrneyfis preferably relieved toward the charging end of the furnace, as shown in Figure 4, so as to cooperate with the beveled surface of the groove i2 inthe bottom of the furnace't'o completely seal that edge of the door. sides of the frame are also prefer-ably relieved toward the charging end of th`furnaoe, as shown in Figure 5, to cooperatewith theinner beveled edges of the guide grooves l0 ofthe side Walls of the chamber to completely sealthese edgeswhen the` door is in position inthe heating chamber.

There ,is sho-wn in. Figure 6 a modified form of construction. of the guide grooves in the side Walls'of the heating chamber. In this construcv Y the furnace.' When the doorsv are in positionin the guide grooves lo of the heating chamber, they are, of course,A arranged at an acute angle to the floor of the chambertoward the charging end of the-furnaceI due to the fact that the guide grooves are arranged at such an-nangle. Such an arrangement allows the `doors to lie against the inner beveled edges of the guide-grooves Il! of the side Walls and the groove l2 of the floor due to their own Weight, thereby completely sealing that portion of the heating chamber to be heated and used, from that portion Whichy is not `tobe used, It is .preferable that a gas-escapement valve`22 be rpositioned inthe top of theffurnace communicating with the heating chamber enclosed by each of @the fire gates so as to lallovv a meansofescapement for the smallleakage of gasthrough the doors from the used` portion of the heating chamber to the unused portion thereof, Which may occur` and ,collectinhthese chambers When the furnace is in use, thereby preventing the l danger of explosion.

Irwin be `ondersteou that it would not be necessary to provide a` plurality of doors Abut one doo-r could be provided andv moved from one position to the other as desired; and, furthermore, `the doors need not loeA inserted fromthe top of the? furnace as shown in the drawings but` the `furnace may be constructed and the doors arranged so as to `slide into the heating chamber from the side thereof. Y

As a result of my invention, itwill be seen that the burners positioned'between the` `fire gate and la charging door `at the charging4 end of the furnace need be used onlyf to heat yany load therein and that therburners in back of the fire ydoor neednot be usedand can be closed 'bymeans of theurvalves r`@,thereby resulting, in asaving of The"y fuel. With such an arrangement, the size of the heating chamber can be increased orl decreased, as desired, according to the size of the load or charge to be heated.

While I have shown and described an embodiment of my invention, it will be understood that this embodiment is merely for the purpose of illustration and description and that various other forms may be devised Within the scope of my invention, as dened in theappended claims..

i. An elongated heating furnace of the class described having one end thereof permanently vclosed and an opening in the opposite end for vcharging the same, and means associated With that portion of the furnace toward the closed the heating` chamber therein.

2. An elongated furnace of lthe class described having one end thereof permanently closed and anhopening in the opposite end for charging the same, afplurality of yspaced apart doors associated With that portion of the furnace toward Athe closed end thereof, said doors being constructed and arranged so that Vany one of them may be positioned in said'furnaoe so as to reduce the length and size of the yheating chambertherein'; f f

3. An elongated furnace of 'the'class described having one end thereof permanently closed and an opening in the opposite end for charging the same, a plurality of spaced apart doors associatedV with that portionv of tl'1e"furnac'e towardV the closed end thereof, said doors arranged subst-ane tiall'y for vertical movement into and out of said furnace wherebyl the movement ofany oneof them into said' furnace provides'a predetermined sized heating chamber therein.

` 4. An elongated furnaceof the class described having one end thereof permanently' closed and an opening in the opposite end for charging the same, said furnace having a plurality of openings spaced apart at predetermined intervals and arranged in one Wall thereof in that portion of the furnacetowardits closed end and communioating' With the heating chamber therein,

'endthereof for varying the length and'size of.

`and means adaptedto'be inserted through any l' one of said openings into said rfurnace 'so as to reduce the length and size of the'heating chamber therein.

` 5. An elongated furnace ofthe class described having' one end `thereof permanently closed and' an opening in the opposite end for charging the same, said furnace'having a plurality of spaced apart openings arranged in the, top Wall thereof in that portion of the furnace toward its'closed end,va v setof guide grooves arranged in the side Walls and floor of said furnace opposite each of said openingswith the grooves in said side Walls being disposed at an acute angle Withjthe floor toward 'the charging end of the furnaceand with each o-f the grooves beveled toward said charging. end, and a door arranged opposite each of said openings with each of said doors having edges corresponding with said grooves 4so' that `any one of said doors maybe inserted through its opposed 

